This is one of the perverse effects of limits on new construction. Since builders can only build so much, they naturally focus on the high-end where profits are

This is one of the perverse effects of limits on new construction. Since builders can only build so much, they naturally focus on the high-end where profits are fattest. In a well-functioning market there is only so much demand for luxury housing so they would also build smaller, less expensive stuff as well, but they can't